The head of China's environmental protection agency has resigned following a chemical spill that polluted a major river and forced the shutdown of water supplies in parts of the country's northeast.

The official Xinhua news agency reported the resignation Friday, but did not provide details.

Meanwhile, China's foreign ministry says it is sending Russia 150 tons of activated charcoal to help filter pollution from the toxic chemical slick moving along the Amur river toward the Russian city of Khabarovsk.

Earlier this week, Russian environmental officials reported higher levels of benzene in the river, but said it is not clear if the toxic chemical is from the massive spill in China two weeks ago.

A November 13 explosion at a factory dumped 100 tons of poisonous chemicals into China's Songhua river.